Performance of preparative CCC (countercurrent chromatography) systems mainly depends upon the amount of the stationary phase retained in the column, which determines both the resolving power of the solute peaks and the sample loading capacity. Various CCC systems developed in the past (see Y. Ito, J. Biochem, Biophys. Met., 5 (1981) 105) are usually capable of yielding retention of the stationary phase of no more than 50% of the total column space. This maximum attainable retention level tends to fall rather sharply with the application of higher flow rates of the mobile phase, resulting in loss of peak resolution. Consequently, the applicable flow rate has become one of the major limiting factors in CCC, and the methods require relatively long separation times ranging from overnight to several days to complete a sizable separation. There is a definite need for an improved CCC system which can perform using a high feed rate of the sample solution and which requires a substantially shorter separation time (see Y. Ito, J. Chromatogr., 207 (1981) 161).